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Sendip packet crafting tool: How to send bad checksum TCP packets
https://forum.ivorde.com/sendip-packet-crafting-tool-how-to-send-bad-checksum-tcp-packets-t16151.html
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Author:  mandrei99 [ Tue Jan 28, 2014 5:52 am ]
Post subject:  Sendip packet crafting tool: How to send bad checksum TCP packets

Following sendip command will send TCP packets with bad checksum.

Code:
# sendip  -p ipv4 -p tcp -is 10.0.1.2 -iv 4 -ip 6 -ic 2342352 -ts 1000 -td 80 -tc 234235235 172.16.2.2


Following a tcpdump snapshot of the packet:
Code:
10:49:53.952912 IP (tos 0x0, ttl 255, id 61754, offset 0, flags [none], proto TCP (6), length 40)
    10.0.1.2.1000 > 172.16.2.2: Flags [S], cksum 0x2563 (incorrect -> 0xd933), seq 2806054912, win 65535, length 0



See the incorrect tcp checksum.

Author:  ladlasheikh [ Fri Mar 27, 2015 7:40 am ]
Post subject:  Re: Sendip packet crafting tool: How to send bad checksum TCP packets

will send TCP packets with bad checksum?great

Author:  lizamare [ Wed Apr 15, 2015 2:02 am ]
Post subject:  Re: Sendip packet crafting tool: How to send bad checksum TCP packets

Ok i understand what you are saying but i think there should be more comments about the topic started initially, Thanks

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